With the development of wireless communication technologies, a Fixed Wireless Terminal (FWT) is applied to many communication systems that require signaling transmission. For example, as shown in FIG. 1, the FWT in the system can receive a voice signal from traditional devices such as fixed telephone sets and fax machines, convert the voice signal into a Dual Tone Multi Frequency (DTMF) signaling, and send the dual tone multi frequency signaling to a base station through a wireless network. The base station recovers the voice signal from the dual tone multi frequency signaling, and sends the voice signal to another fixed telephone set through a server in a public switched telephone network, thereby implementing accurate transmission of dual tone multi frequency signaling between two traditional telephone sets. In that process, after converting a voice signal into a dual tone multi frequency signaling and sending it to the base station, the FWT needs to wait for a feedback command from the base station. The FWT does not send a next dual tone multi frequency signaling to the base station until a feedback command is received from the base station.
The FWT sends a signaling to the base station, the base station receives the signaling, and the base station sends a feedback command to the FWT. Time required in this process is T, and a time interval between voice signals sent by the devices such as a fixed telephone set and a fax machine is t. Generally, T is less than or equal to t, that is, the time interval between signalings is generally greater than the time required for the FWT to wait for the feedback command. For example, a user dials 144, a time interval between 1 and 4 is 200 ms, a time interval between 4 and 4 is 210 ms, and the time spent by the FWT in receiving, converting and sending the voice signal of the digit 1 at the intervals until receiving a feedback command from the base station is 110 ms. That is, the FWT has received the feedback command before receiving the next voice signal so that the FWT can send a dual tone multi frequency signaling to the base station directly after receiving the next voice signal and converting it into the dual tone multi frequency signaling.
Further, many devices are capable of sending voice signals automatically. For example, in a security and defense system, an alarm host automatically sends multiple voice signals to a server in an alarm center at equal time intervals through a Public Switched Telephone Network (PSTN), where the time intervals are small, such as 50 ms.
The prior art has the following problems:
When a device sends voice signals automatically, because the time interval between voice signals is small, the time interval between signalings converted from the voice signals is small. If the FWT in the prior art processes the voice signals, before the FWT receives a feedback command from the base station, unsent signaling will congest the FWT; the FWT does not send a next signaling to the base station until it receives the feedback command in response to the previous signaling, which leads to a long period of time spent by the FWT in sending the signaling. For example, in many security and defense systems, the alarm host uses the FWT to send a voice signal to the alarm center for raising an alarm. However, because the time spent in sending the signaling is long, the alarm center suffers from a too great delay in receiving the voice signal for raising an alarm, which even leads to an alarm failure and reduces reliability of the security and defense system.